The explosion in the soundcard market has given many computer users the opportunity to get involved in serious music-making for the first time. For others it's been the source of frustration as they struggled to get their CPUs to talk to a new system extension. For those looking to buy a sound card, there is also confusion over which card to choose and what kind of quality to expect. Here with help for one and all is Ian Waugh...

Connectivity - that's the name of the game. Impressive as they may be, modern computers can't do everything. Not without a bit of help. PCs and Apple Macs, for example, contain internal slots capable of taking an enormous range of plugin cards to help them perform other functions.

The PC is the most expandable of all computers, and cards available include modems (for communicating with other computers), scanner cards, and maths cards (for speeding up mathematical calculations). Most PCs already have some slots taken up with a card to control their hard disk and a video display card which produces the picture you see on the monitor.

There is also a wide range of cards to interest musicians and people working in multimedia. Video capture cards (not to be confused with video display cards) let you store video clips on disk for editing. And, of course, there are sound cards. These started life as a means of adding synthesised sounds to the PC (which otherwise only has a paltry single-sound beep), primarily for games, but they have now developed into veritable jacks-of-all-trades with facilities such as digital recording and playback, and also interfacing for MIDI and CD-ROM players. Some use quite sophisticated forms of synthesis and are capable of high-quality digital recording.

Apple Macs have card slots, too. The most well-known is the NuBus slot, but the LC family have PDS slots which, though taking up less space, work in a similar way. These are used for coprocessors to speed up maths functions, graphics cards for special video displays and networking cards for connecting the Mac to other Macs or a PC. Most of the Mac sound cards are used for digital recording. As far as I am aware there are currently no Mac cards containing sounds (other than Sample Cell II which is more akin to a sampler), but please put me right on this one if there are.

As with most things Mac, you can usually plug a card into your computer, boot your application and start using it. As with all things PC, plugging in cards isn't likely to be as straightforward...

PCs have 8-bit and 16-bit card slots. You can easily see which is which because 16-bit slots are longer than 8-bit ones (most PCs with 16-bit slots also have at least one 8-bit slot) and there is a small gap between the rows of connectors. You can use most 8-bit cards in a 16-bit slot quite happily. Stereo sound cards and cards with 16-bit sampling resolution will be 16-bit cards.

But plugging the card in is the easy bit. You then have to configure it. Depending on the card's facilities this could involve you in port addresses, DMA and IRQ settings. It's all part of the process of telling the computer exactly where the sound card is in relation to the system and it could be argued that this simply reflects the PC's flexibility, but it's a flexibility that can lead you into problems - problems which the Mac user doesn't have to worry about as everything is taken care of automatically.

If you don't have any other devices in your PC, you may be able to simply plug in and go. However, like as not you'll have to change at least some of these settings. The better software supplied with the cards lets you test the system and make changes through the program - although if there is a conflict (that is, if another card is using the same IRQ or DMA channel), it's not always easy to track down. Settings can also usually be changed on the card itself using DIP switches or by changing the position of jumper pins.

When you've got that working you then have to install some drivers to control the card. There will be different drivers for DOS and Windows applications. Usually installation is fairly easy although this depends on the installation routines supplied. The ethos behind Windows means that an application does not have to know exactly what is connected to the system. It simply talks to the driver and the driver sends the necessary instructions to the hardware. Windows comes with several drivers which you can see in the Drivers section of the Control Panel.

There are two main PC sound-card standards, both named after the cards that started the trend. The Ad Lib card was taken as the standard for music and most sound cards support this. The Sound Blaster added digital audio and the ability to play back sampled speech and sound effects. It's also backwards compatible with the Ad Lib card and unless your budget is limited, Sound Blaster compatibility should be your aim. But sound-card technology moves on and more sophisticated standards are starting to appear. Sound Blaster Pro offers 20-voice stereo sound and many games now have this as an option. Look for Pro compatibility if you're serious about your games.

The other emerging standard is GM (General MIDI) and some cards contain a set of GM sounds which can be particularly useful for the muso on a budget - GM and digital recording in one package.

But given that most of these cards cost well under £200, just what kind of audio quality are we talking about here? Well, this is where the cracks begin to show. Most of the cheaper cards use the Yamaha YM3812, a 2-operator FM chip, which may be adequate for games but it would hardly pass muster even at a karaoke night. Cards with the Yamaha OPL3 chip are noticeably better although it's still FM and well below current state-of-the-art sound synthesis. Still, it is GM-compatible and that must earn it a few extra brownie points.

If you want sounds more in keeping with today's standards then you need to look at wavetable synthesis cards such as the Orchid Soundwave 32, the Gravis Ultrasound and the Wave Blaster add-on as well as the Roland SCC-1 and the Turtle Beach cards. The Multisound card, for example, contains the equivalent of a Proteus 1/XR synth!

Digital audio, again, was originally developed for games and based around 8-bit sampling but the development of stereo 16-bit cards supporting sample rates up to 44.1 KHz raised the quality, certainly to that of good demo standards. If you compare these with dedicated digital audio systems it must be remembered that sound cards are called upon to do several tasks while digital audio systems are designed to do one job well and usually include additional hardware to do it. Dedicated systems will have superior digital converters so the sound quality is bound to be better.

As with most things, you get what you pay for, but if you are on a budget sound cards really are worth considering.

Where most of the cards fall down is the recording software which is not as sophisticated as dedicated software such as Turtle Beach's Wave for Windows, Voyetra's Audio View or Innovative's SAW. Still, you can often use this software with a card of your choice. SAW, for example (watch out for a review in MT very soon), is compatible with the Sound Blaster ASP.

If you want to move more upmarket, there are several dedicated digital audio cards to choose from for both the PC and the Mac. PC cards such as the CardD+ and the Turtle Beach cards are still very affordable and capable of producing excellent results.